1. Field of the Invention
The invention relates to a cassette holder for a magnetic-tape recording/playback apparatus, and more particularly to a holder which is pivotable about a pivoting axis and is adapted to receive cassettes which are provided with two coplanar adjoining magnetic-tape reels which are rotatable about parallel axes of rotation and are situated in a cassette housing. Such a housing has two major walls on both sides of the reels, interconnected by two closed side walls, a substantially closed rear wall and by a front wall with openings for the passage of components of a recording/playback apparatus, such as a magnetic recording/playback head, an erase head, and a pressure roller etc. The side walls are provided with projection portions in the form of ridges, which extend along a part of the side wall and parallel to the major walls and are situated near the front wall at half the height of the side wall, so that locally the cassette has a greater width, and furthermore each of the major walls has a projecting portion in the form of a raised portion which extends over the openings in the front wall, so that locally the cassette has a greater thickness.
The cassette holder itself a first wall which is parallel to the major walls of an inserted cassette and an axial second wall which is parallel thereto; two side walls; a bottom wall which faces the pivoting axis and an open at least substantially top side which is remote from the pivoting axis, whose opening serves as a cassette insertion opening for the insertion of a cassette into the cassette holder; stop means which cooperate with projecting portions of the cassette housing when a cassette is inserted into the cassette holder, so as to avoid an incorrect position of the cassette in the cassette holder, a position in which the substantially closed rear wall of the cassette would be oriented towards the bottom wall of the cassette holder; and guide means for the major walls of the cassette housing near its side walls and beside its locally thickened portion during insertion of a cassette, having two guide ridges which extend in the longitudinal direction of and near the side walls of the cassette holder.
In the present stage of development of magnetic tape recording/playback apparatus adapted for use in conjunction with the well-known Compact Cassettes, the so-called cassette recorders, a distinction can be made between two main categories of cassette recorders. One category is cassette recorders with a horizontal cassette holder (the so-called horizontal cassette recorders), and the other category is recorders having a vertical cassette holder (the so-called vertical cassette recorders). Of these two categories the former was the first to appear on the market. In such equipment of this category the cassette holder is pivotable about an axis which is disposed near the rear wall of a cassette contained in the cassette holer. This permits convenient use of the cassette recorder, because in this way a user can insert a cassette into the cassette holder with a smooth movement. Moreover, the components of the cassette recorder which cooperate with the magnetic tape in the cassette, such as the magnetic heads and the pressure roller, are located at the front of the cassette recorder facing the user. These components can be controlled by means of the controls, such as push-buttons, which are situated at this location. In horizontal cassette recorders the front side of an inserted cassette, in which the openings are formed, is consequently always located at the open topside of the cassette holder. Thus, incorrect insertion of a cassette can be prevented simply. Both the locally widened portion and the locally thickened portion of the cassette are situated at the side which is located nearer the open front side of the cassette. Thus, stop means may be incorporated in the cassette holder which permit the insertion of the thinner and narrower part of the cassette over the full length of the cassette holder, but which enable the insertion of the wider and thicker part of the cassette over a part of the length only. Compact Cassettes are labelled in such a way that the cassette, when in the operating position in a horizontal cassette recorder, is correctly positioned to enable it to be read by a user.
In vertical cassette recorders the pivoting axis of the cassette holder is generally situated at the side which faces the bottom of the apparatus, where the components of the apparatus which co-operate with the magnetic tape in the cassette and the controls are also located. However, in this equipment the cassette should be inserted with its thickened and widened portion foremost. Thus, in comparison with a horizontal cassette recorder the position of a cassette relative to the pivoting axis of the cassette holder is exactly the other way round. This complicates prevention of incorrect insertion of the cassette into the cassette holder.
2. Description of the Prior Art
In a known vertical cassette recorder moving components are mounted in the cassette holder, which components engage the raised portion of the major wall of the cassette, sense said raised portion, and then actuate moving stop means in such a way that the cassette can be fully inserted into the cassette holder only if the raised portion has passed first. The raised portion causes a tilting plate to tilt, which plate is pivotable to a limited extent about an axis parallel to the pivoting axis of the cassette holder and is journalled on the cassette holder. A stop pin, which is pushed away by the front of the cassette. If the cassette is incorrectly inserted into the cassette, is mounted on a resiliently pivotable lever holder, the tilting plate is not tilted and the stop pin is retained by the tilting plate. Thus, as described in U.S. Pat. No. 3,764,089 the cassette cannot be inserted any further and is ejected by the resiliently pivotable lever.